Artificial membranes are being prepared containing myelin lipids and one of the following myelin proteins: Myelin basioprotein (MBP); major glycoprotien of PNS (Po protein); and other major proteins as isolation procedures become available. The purpose of the study is to image the proteins individually in bilayer membranes by means of X-ray diffraction analysis. These images then will be used to interpret the electron-density profiles obtained for native PNS (and CNS) myelins; the native profiles show a number of proteins together in the bilayer membrane, and the individual species of proteins may not be distinguished readily from one another.